Song and Score? Score is understandable, I guess, although I wonder how many people will have seen The Amazing Mrs. Holliday, Commandos Strike at Dawn, Hi Diddle Diddle, The Kansan and Victory Through Air Power (not to mention every single one of the eleven other nominees) and remember their scores well enough to make a decent and educated vote. Once we get into the years of smaller nomination pools, it'll be different, obviously, but in those early years it won't make much sense.
Song, though. Do we really want to go through months and months of polls to end up voting on which song is the best out of "We Belong Together", "I See the Light", "If I Rise" and "Coming Home"? I mean, really? The thing that makes these polls good and interesting is the conversation they generate, and if we're being honest, the polls are by far the main conversation piece on the board from March through November. I just don't see much interesting conversation coming from a poll about "High Hopes" vs. "Strange Are the Ways of Love".
My personal choice would be Cinematography, followed by the Writing Categories (which would give me a chance to to finally watch some movies I've been putting off).